-4x2 +x +3 = 0
ax2 bx c = 0
a = -4
b = 1
c = 3
Δ = b2-4ac
Δ = ² - (4 * -4 * 3)
Δ = 1 - (4*-12)
Δ = 1 - (-48)
Δ = 49 Δ > 0
-4x2+x+3=0
x = -b ∓ √Δ 2a
x' = -1 - √49 2*-4 = -1 - 7.0 -8 = -8.0 -8 = 1.0
x" = -1 + √49 2*-4 = -1 + 7.0 -8 = 6.0 -8 = -0.75
x' = 16.0
x" = -12.0
S = {x ∈ R / x' = 16.0, x" = -12.0 }